Field Notes

Sherman Island: 2014-02-25 10:40:00 (DOY 56)
Author: Cove Sturtevant
Others: Patty

Summary: Plants growing. Cows trampled inside of tower fence and chewed wires. Everything fixed. Regular fieldwork. Data download. Need replacement LED cover.

Sherman
2014-02-25

We arrived about 10:40 PST after dropping Joe off at Mayberry to improve the solar panel setup. It was sunny, warm, and breezy. The site has benefitted from the warming weather and recent rains. There was an extensive green grass layer and green leaves at the base of the standing pepperweed skeletons.

When Patty and I got to the tower we noticed that the area inside the fence looked rather different; most of the brush was gone and overall it looked quite sparse (see photos). Well, this was because the cows had gotten in and trampled everything! They trod over the soil CO2 system and soil respiration collars, chewed through a bunch of thermocouple wires and the PRT wire from the radiometer, and pulled out the SDM connection from the 7500 to the CR1000.

Surprisingly, nothing was permanently damaged. Patty and I repaired the fence, fixed wires, and reconnected everything. I downloaded data. At the end, Patty did spectral while I did well depth and a vegetation height survey. No soil respiration measurements since the collars were reseated. We forgot the moisture point equipment.

7500 readings:
CO2: 17.4 mmol m-3 (same after cleaning)
H2O: 540 mmol m-3 (same after cleaning)
Diag: 247 (same after cleaning)
P = 101.7 kPa
T = 21.6 C
Sos: 343.0 m s-1

LGR readings: 2.11 ppm, 10:52, 21.28 C, 74.7 Torr (adjusted to 144.9), 14.80 us, 10 Hz

Met looked good after fixing chewed wires.
Cleaned radiation sensors. The top LED sensor has a puncture in the wafer. Needs replacement.

After Patty fixed the soil CO2 system, all was working well. Profile B stills look wonky, but Patty thinks this might be because the sensor at the top of the profile has a different max concentration than the lower sensors.

Veg Height (cm): Tape measure from ground to top of plant - short green grass layer and new green leaves at base of pepperweed skeletons
3, 0, 3, 7, 6, 2, 10, 5, 1, 4, 6, 9, 1, 2, 0, 8, 0, 6, 1, 8, avg = 4.1, stdev = 3.24

2 photos found

20140225SI_CowTrampled.jpg ( 2014-02-25 11:22:13 ) Full size: 1296x968
Cows breached fence